kubeasz/tools/kubetail

416 lines
13 KiB
Bash

#!/bin/bash
# https://github.com/johanhaleby/kubetail/blob/master/kubetail
if [ -z "${KUBECTL_BIN}" ]; then
if hash kubectl 2>/dev/null; then
KUBECTL_BIN='kubectl'
elif hash kubectl.exe 2>/dev/null; then
KUBECTL_BIN='kubectl.exe'
elif hash microk8s 2>/dev/null; then
KUBECTL_BIN='microk8s.kubectl'
fi
fi
if ! hash "${KUBECTL_BIN}" 2>/dev/null; then
echo >&2 "kubectl is not installed"
exit 1
fi
readonly PROGNAME=$(basename $0)
calculate_default_namespace() {
local config_namespace=$(${KUBECTL_BIN} config view --minify --output 'jsonpath={..namespace}')
echo "${KUBETAIL_NAMESPACE:-${config_namespace:-default}}"
}
# Sets default color ouput to 'false' if output is not a terminal
terminal_aware_default_color=line
[ ! -t 1 ] && terminal_aware_default_color=false
default_previous="${KUBETAIL_PREVIOUS:-false}"
default_since="${KUBETAIL_SINCE:-10s}"
default_namespace=$(calculate_default_namespace)
default_follow="${KUBETAIL_FOLLOW:-true}"
default_prefix="${KUBETAIL_PREFIX:-true}"
default_line_buffered="${KUBETAIL_LINE_BUFFERED:-}"
default_colored_output="${KUBETAIL_COLORED_OUTPUT:-$terminal_aware_default_color}"
default_timestamps="${KUBETAIL_TIMESTAMPS:-}"
default_jq_selector="${KUBETAIL_JQ_SELECTOR:-}"
default_skip_colors="${KUBETAIL_SKIP_COLORS:-7,8}"
default_tail="${KUBETAIL_TAIL:--1}"
default_show_color_index="${KUBETAIL_SHOW_COLOR_INDEX:-false}"
namespace="${default_namespace}"
follow="${default_follow}"
prefix="${default_prefix}"
line_buffered="${default_line_buffered}"
colored_output="${default_colored_output}"
timestamps="${default_timestamps}"
jq_selector="${default_jq_selector}"
skip_colors="${default_skip_colors}"
tail="${default_tail}"
show_color_index="${default_show_color_index}"
if [[ ${1} != -* ]]
then
pod="${1}"
fi
containers=()
selector=()
regex='substring'
previous="${default_previous}"
since="${default_since}"
version="1.6.19-SNAPSHOT"
dryrun=false
cluster=""
namespace_arg="-n ${default_namespace}"
usage="${PROGNAME} <search term> [-h] [-c] [-n] [-t] [-l] [-f] [-d] [-P] [-p] [-s] [-b] [-e] [-j] [-k] [-z] [-v] [-r] [-i] -- tail multiple Kubernetes pod logs at the same time
where:
-h, --help Show this help text.
-c, --container The name of the container to tail in the pod (if multiple containers are defined in the pod).
Defaults to all containers in the pod. Can be used multiple times.
-t, --context The k8s context. ex. int1-context. Relies on ~/.kube/config for the contexts.
-l, --selector Label selector. If used the pod name is ignored.
-n, --namespace The Kubernetes namespace where the pods are located. Defaults to \"${default_namespace}\".
-f, --follow Specify if the logs should be streamed. (true|false) Defaults to ${default_follow}.
-d, --dry-run Print the names of the matched pods and containers, then exit.
-P, --prefix Specify if add the pod name prefix before each line. (true|false) Defaults to ${default_prefix}.
-p, --previous Return logs for the previous instances of the pods, if available. (true|false) Defaults to ${default_previous}.
-s, --since Only return logs newer than a relative duration like 5s, 2m, or 3h. Defaults to ${default_since}.
-b, --line-buffered This flags indicates to use line-buffered. (true|false) Defaults to ${default_line_buffered:-false}.
-e, --regex The type of name matching to use (regex|substring). Defaults to ${regex}.
-j, --jq If your output is json - use this jq-selector to parse it. Defaults to \"${default_jq_selector}\".
example: --jq \".logger + \\\" \\\" + .message\"
-k, --colored-output Use colored output (pod|line|false).
pod = only color pod name, line = color entire line, false = don't use any colors.
Defaults to ${default_colored_output}.
-z, --skip-colors Comma-separated list of colors to not use in output.
If you have green foreground on black, this will skip dark grey and some greens: -z 2,8,10
Defaults to: ${default_skip_colors}.
--timestamps Show timestamps for each log line. (true|false) Defaults to ${default_timestamps:-false}.
--tail Lines of recent log file to display. Defaults to ${default_tail}, showing all log lines.
-v, --version Prints the kubetail version.
-r, --cluster The name of the kubeconfig cluster to use.
-i, --show-color-index Show the color index before the pod name prefix that is shown before each log line.
Normally only the pod name is added as a prefix before each line, for example \"[app-5b7ff6cbcd-bjv8n]\",
but if \"show-color-index\" is true then color index is added as well: \"[1:app-5b7ff6cbcd-bjv8n]\".
This is useful if you have color blindness or if you want to know which colors to exclude (see \"--skip-colors\").
Defaults to ${default_show_color_index}.
examples:
${PROGNAME} my-pod-v1
${PROGNAME} my-pod-v1 -c my-container
${PROGNAME} my-pod-v1 -t int1-context -c my-container
${PROGNAME} '(service|consumer|thing)' -e regex
${PROGNAME} -l service=my-service
${PROGNAME} --selector service=my-service --since 10m
${PROGNAME} --tail 1"
if [ "$#" -ne 0 ]; then
while [ "$#" -gt 0 ]
do
case "$1" in
-h|--help)
echo "$usage"
exit 0
;;
-v|--version)
echo "$version"
exit 0
;;
-c|--container)
containers+=("$2")
;;
-e|--regex)
if [ "$2" = "substring" ]; then
regex="substring"
else
regex="regex"
fi
;;
-t|--context)
context="$2"
;;
-r|--cluster)
cluster="--cluster $2"
;;
-l|--selector)
selector=(--selector "$2")
pod=""
;;
-d|--dry-run)
dryrun=true
;;
-p|--previous)
if [ "$2" = "false" ]; then
previous="false"
else
previous="true"
fi
;;
-s|--since)
if [ -z "$2" ]; then
since="${default_since}"
else
since="$2"
fi
;;
-n|--namespace)
if [ -z "$2" ]; then
# using namespace from context
:
else
namespace_arg="--namespace $2"
fi
;;
-f|--follow)
if [ "$2" = "false" ]; then
follow="false"
else
follow="true"
fi
;;
-P|--prefix)
if [ "$2" = "false" ]; then
prefix="false"
else
prefix="true"
fi
;;
-b|--line-buffered)
if [ "$2" = "false" ]; then
line_buffered=""
else
line_buffered="| grep - --line-buffered"
fi
;;
-k|--colored-output)
if [ -z "$2" ]; then
colored_output="${default_colored_output}"
else
colored_output="$2"
fi
;;
-j|--jq)
if [ -z "$2" ]; then
jq_selector="${default_jq_selector}"
else
jq_selector="$2"
fi
;;
-z|--skip-colors)
if [ -z "$2" ]; then
skip_colors="${default_skip_colors}"
else
skip_colors="$2"
fi
;;
--timestamps)
if [ "$2" = "false" ]; then
timestamps="$1=$2"
else
timestamps="$1"
fi
;;
--tail)
if [ -z "$2" ]; then
tail="${default_tail}"
else
tail="$2"
fi
;;
-i|--show-color-index)
if [ -z "$2" ]; then
show_color_index="${default_show_color_index}"
else
show_color_index="$2"
fi
;;
--)
break
;;
-*)
echo "Invalid option '$1'. Use --help to see the valid options" >&2
exit 1
;;
# an option argument, continue
*) ;;
esac
shift
done
else
echo "$usage"
exit 1
fi
# Join function that supports a multi-character separator (copied from http://stackoverflow.com/a/23673883/398441)
function join() {
# $1 is sep
# $2... are the elements to join
local sep="$1"
shift
local F=0
for x in "$@"
do
if [[ F -eq 1 ]]
then
echo -n "$sep"
else
F=1
fi
echo -n "$x"
done
echo
}
# Check if pod query contains a comma and we've not specified "regex" explicitly,
# if so we convert the pod query string into a regex that matches all pods seperated by the comma
if [[ "${pod}" = *","* ]] && [ ! "${regex}" == 'regex' ]; then
# Split the supplied query string (in variable pod) by comma into an array named "pods_to_match"
IFS=',' read -r -a pods_to_match <<< "${pod}"
# Join all pod names into a string with ".*|.*" as delimiter
pod=$(join ".*|.*" "${pods_to_match[@]}")
# Prepend and initial ".*" and and append the last ".*"
pod=".*${pod}.*"
# Force the use of regex matching
regex='regex'
fi
grep_matcher=''
if [ "${regex}" == 'regex' ]; then
echo "Using regex '${pod}' to match pods"
grep_matcher='-E'
fi
# Get all pods matching the input and put them in an array. If no input then all pods are matched.
matching_pods=(`${KUBECTL_BIN} get pods ${context:+--context=${context}} "${selector[@]}" ${namespace_arg} ${cluster} --field-selector=status.phase=Running --output=jsonpath='{.items[*].metadata.name}' | xargs -n1 | grep --color=never $grep_matcher "${pod}"`)
matching_pods_size=${#matching_pods[@]}
if [ ${matching_pods_size} -eq 0 ]; then
echo "No pod exists that matches ${pod}"
exit 1
fi
color_end=$(tput sgr0)
# Wrap all pod names in the "kubectl logs <name> -f=true/false" command
display_names_preview=()
pod_logs_commands=()
i=0
color_index=0
function next_col {
potential_col=$(($1+1))
[[ $skip_colors =~ (^|,)$potential_col($|,) ]] && echo `next_col $potential_col` || echo $potential_col
}
# Allows for more colors, this is useful if one tails a lot pods
if [ ${colored_output} != "false" ]; then
export TERM=xterm-256color
fi
# Function that kills all kubectl processes that are started by kubetail in the background
function kill_kubectl_processes {
kill 0
}
# Invoke the "kill_kubectl_processes" function when the script is stopped (including ctrl+c)
# Note that "INT" is not used because if, for example, kubectl cannot find a container
# (for example when running "kubetail something -c non_matching")
trap kill_kubectl_processes EXIT
# Putting all needed values in a variable so that multiple requests to Kubernetes api can be avoided, thus making it faster
all_pods_containers=$(echo -e `${KUBECTL_BIN} get pods ${namespace_arg} ${context:+--context=${context}} --output=jsonpath="{range .items[*]}{.metadata.name} {.spec['containers', 'initContainers'][*].name} \n{end}"`)
for pod in ${matching_pods[@]}; do
if [ ${#containers[@]} -eq 0 ]; then
pod_containers=($(echo -e "$all_pods_containers" | grep $pod | cut -d ' ' -f2- | xargs -n1))
else
pod_containers=("${containers[@]}")
fi
for container in ${pod_containers[@]}; do
[ ${matching_pods_size} -eq 1 -a ${#pod_containers[@]} -eq 1 ] && single_stream="true" || single_stream="false"
if [ ${colored_output} == "false" ] || [ ${single_stream} == "true" ]; then
color_start=$(tput sgr0)
color_index_prefix=""
else
color_index=`next_col $color_index`
color_start=$(tput setaf $color_index)
color_index_prefix=`if [ ${show_color_index} == "true" ]; then echo "${color_index}:"; else echo ""; fi`
fi
if [ ${#pod_containers[@]} -eq 1 ]; then
display_name="${pod}"
else
display_name="${pod} ${container}"
fi
if [ ${colored_output} == "false" ]; then
display_names_preview+=("${display_name}")
else
display_names_preview+=("$color_index_prefix${color_start}${display_name}${color_end}")
fi
if [ ${prefix} == "false" ]; then
prefix_line=""
else
if [ ${colored_output} == "false" ]; then
prefix_line="[${display_name}] "
else
prefix_line="${color_start}[${color_end}${color_index_prefix}${color_start}${display_name}]${color_end} "
fi
fi
if [ ${colored_output} == "false" ] || [ ${colored_output} == "pod" ]; then
colored_line="${prefix_line}\$REPLY"
else
colored_line="${prefix_line}${color_start}\$REPLY${color_end}"
fi
kubectl_cmd="${KUBECTL_BIN} ${context:+--context=${context}} logs ${pod} ${container} -f=${follow} --previous=${previous} --since=${since} --tail=${tail} ${namespace_arg} ${cluster}"
colorify_lines_cmd="while read -r; do echo \"$colored_line\" | tail -n +1; done"
if [ "z" == "z$jq_selector" ]; then
logs_commands+=("${kubectl_cmd} ${timestamps} | ${colorify_lines_cmd}");
else
logs_commands+=("${kubectl_cmd} | jq --unbuffered -r -R --stream '. as \$line | try (fromjson | $jq_selector) catch \$line' | ${colorify_lines_cmd}");
fi
# There are only 11 usable colors
i=$(( ($i+1)%13 ))
done
done
# Preview pod colors
echo "Will tail ${#display_names_preview[@]} logs..."
for preview in "${display_names_preview[@]}"; do
echo "$preview"
done
if [[ ${dryrun} == true ]];
then
exit 0
fi
# Join all log commands into one string separated by " & "
command_to_tail=$(join " & " "${logs_commands[@]}")
# Aggregate all logs and print to stdout
# Note that tail +1f doesn't work on some Linux distributions so we use this slightly longer alternative
# Note that if --follow=false, then the tail command should also not be followed
tail_follow_command="-f"
if [[ ${follow} == false ]];
then
tail_follow_command=""
fi
tail ${tail_follow_command} -n +1 <( eval "${command_to_tail}" ) $line_buffered